(cba:news) Musings on Nova Del 2013, and some other novae, actual and imagined

[Joe Patterson]

Hi Tony et al.,

    It's kind of a celebrity object right now, and too bright for our 
CCDs.  Plus it's quite unlikely now to show rapid variability, because 
the "photosphere" is thousands of WD-radii in size (the expanding shell 
is a big opaque envelope many times bigger than the entire underlying 
binary).  So I'd rather lie low until the shell goes transparent - 
that's when we can first see down to the inner binary.  Roughly 
speaking, that's when the soft X-rays first appear, or *very* roughly 
when the nova falls about 5 mag.  Others will study this object pretty 
well, now that it has hit the headlines.

    That's all premised on the assumption that it's "just another nova". 
I haven't seen any evidence yet that it's something different... but the 
sky is full of surprises!

    The stars that I'd mainly like to promote this month are V1101 Aql 
and GD 552 ("Cep 1") in the north... BW Scl in the far south... and 
V1432 Aql and V1494 Aql (Nova Aquilae 1999 - now *that* was a sight to 
see!) for any conceivable hemisphere.

    Oh yes, one more, speaking of novae: HR Del.  A nice bright star 
that has been strangely neglected (by us, too) in time-series 
photometry.  There are some hints of multiple periodicities in the 
historical record.  Porb is around 5 hours, so this star does need quite 
long nightly runs.  But it's mighty bright, and for small scopers could 
be a great, great target.

joe



On 8/16/2013 1:05 PM, Anthony J. Kroes wrote:
> Are we interested in this object?  One of my astronomy club members sent me
> the link below and also a picture he took early this morning - a wide field
> shot with a DSLR camera which easily caught the Nova at about magnitude 5.
>
>
>
> http://www.universetoday.com/104103/bright-new-nova-in-delphinus-you-can-see
> -it-tonight-with-binoculars/#more-104103
>
>
>
> Tony Kroes
>
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